There are many good reasons and a few reasons not to do this. This is the system with a front mounted radiator: (It's a little hard to see, but there is a radiator behind the two front fans) And this is the system with a top mounted radiator: One thing I did differently to the other tests I have seen is not locking any fan speeds in the system, so the GPU/Radiator/case fans were set to the default quiet curves. Richard was feeling sick (wanting to throw up) from being thrown around in the race car while trying desperately to concentrate on water levels in clear plastic tubes. A trial fit of the driver's seat. Add to wish list. CDCT60. Jul 1, 2008 18:36:18 GMT -5 . Image thanks to AMR1.uk and “Vantage Summer 2014”. As can be seen, the coolant hose diameter plays a role, and the diameter can be chosen to balance head loss and added water mass to the vehicle. In fact, at Le Mans we lost a door on the main straight at top speed (literally blew off due to the pressure difference inside to outside) and had to reinforce the attachments! Aerodynamicists learn all about the theory and that’s useful for sure and important when pushing the boundaries of the possible but not vital if you have a slightly less advanced airflow related job to do. Nov 4, 2016 #2 Bandalo 2[H]4U. If you mount the radiator and its fans too close to a device pushing air in the opposite direction it can cause a stalemate with the air and in turn give you higher temperatures. I’d like this to be a simple guide to improving some parts of your race car wherever you need to provide passively induced “forced” airflow. When tested this felt like a miracle. To be honest I think this is actually a lovely example. PVC Duct Hose . CTS RADIATOR ALUMINUM MOUNTING BRACKETS . Another duct expander/diffuser I remember well (because it was free performance, but also because it made the team manager sick [he looked a pale shade of green to me after testing]), was fitted to the Nimrod airbox entries – I will explain. The driver commented that he felt like he was being blown out of the cockpit and the brakes ran well within the limits of the temperature paint we put onto the rim of the disks (unlike before). Ducting. Detmar 754 Blower, In-Line 3 Inch Intake X 3 Inch Exhaust, 12 Volt. It is a trick many aero people use in all sorts of applications. The Nimrod had some carefully sculpted NACA ducts in the chassis / cockpit roof to feed the engine airbox. Some other comments about ducting air. We needed the extra length to be able to expand the air back to the area of the radiators. Air cooled VW's present their own problems for radiator installations, particularly the following: All of these result in the radiator installations in previously air cooled VW's tending to be in non ideal locations, which, in turn, means that everything possible should be done to improve their efficiency if they are to work effectively. Air duct, radiator. With a fixed point of blockage (such as a radiator) you can increase the rate of expansion beyond the normal 7 degree limit as you approach the core (aerodynamic blockage) itself. but that’s a good starting point. The trick is to pick the air up in a place where there is plenty of energy and pressure and then to expand it out gently and duct it to exactly where it is needed. : Radiator Installation Design GuideIntroduction: There are a number of basic rules to designing a radiator installation which, if followed, will considerably increase the chances of your installation working properly. It could still house mounting points for the headlights and nose, but would give me the freedom to mount a radiator at any angle or location I wanted (within the confines of the front nose, of course). $27.27. For safety, we fabricated the forward hoop to completely encompass the driveshaft. Get the protection you need by following these steps. Nice radius on the leading edge to ensure there is nothing to trip up the air and the expander is a low angle. There was relatively little water displacement without the extenders and to be honest I don’t remember in which direction the water moved for that baseline test. In any case we needed the drag reduction that the revised bodywork gave us. Two parallel side mounted radiators on either side is less frequently used due to the added weight of coolant lines and tanks. Air flowing near a surface is slowed – you can think of it as feeling friction. If the airbox had high pressure it would start to push the water away from the engine (into the cockpit). This accelerates the air backwards and the reaction of this acceleration against the installation provides a small forward thrust. For a turbo engine multiply by the boost pressure ratio (to atmospheric pressure). Air for the engine is gathered by vents on both sides of the fascia. Hence, unless you have the tools to assess the performance of an exit duct, don’t have one – and put any exit where it will do the least damage (or the most good :-) ). I have seen online that there is some debate on whether front mounted is bad for overall temperatures of your case. Radiators often seem to be installed in a 'minimum effort' kind of way, rather than one with any real engineering intent behind it. Bulkhead Flanges . In addition there is a certain amount of skin friction on both sides of any sheet, so that too has to be taken into account if you put splitters into a duct. I ran it like this for about 6 months, blew up another eg33 and got sick of dealing with their issues, and switched to a ej205 (at which point I changed back to a front mounted radiator to save weight. Display. Of course this is influenced by the speed of the vehicle, the radiator area, heat rejection etc. There are plenty of scientific articles out there that will explain that you need no more than 7 degrees for an expanding duct like this. Add to compare list Add to wishlist. The lack of a factory fitted radiator location, or suitable place into which one can easily be installed. We had no choice but to expand faster than the recommended max of 7 degrees. Ducting. Air is not going to speed up to faster than the car if there is blockage in the duct further down the line, as there always is with brake ducts or radiator ducts. This was the perfect size (not luck) for two 50mm (I think) diameter ducts (on each side). All the air which flows into the duct has to go through the radiator to get out. The entry is a very important thing and sizing the entry is part of it. Sceptics in the team were not convinced that it would make any difference at all. Expanding the air gently is the right thing to do. 2015 BMW S1000RR. Think about what will happen on an airbox in particular if the throttles are closed. These rules seem to be either unknown or ignored by a lot of people coming up with a custom radiator installation for their engine conversion. For this and other reasons, airboxes also have increasing rates of expansion. use a bit of a radius at the leading edge to allow for changes of alignment. PVC Ideas..... ( o \ | / o ) Roadrunna Full Member . Many of the worst examples often seem to be on radiator installations for water cooled engine conversions in previously air cooled Volkswagens. Unfortunately, the brakes overheated and the driver was feeling pretty cooked as well. I’m not even sure if we had a real seat on the passenger side so he was having to hold on to the roll bars at the same time – quite a challenge! Our range of covers standard radiators for all carburetor , SPi and MPi Mini’s, 2 core and 4 core high-flow uprated radiators and high efficiency aluminium radiators for the ultimate in cooling performance . The blockage of the radiator allows faster (more than 7 degrees) when you get close to the surface of the radiator. Thread in 'Technical Questions' started by Polo, Oct 14, 2011. Now to set the scene, this is about road going vehicles with a rear mounted radiator at sustained open road speed ... and from past vehicles I've built for the road (I solved one with ducting, one with extra radiator core (I used two radiators), and the rest with HD fans (Audi ones I think from the A4's, these fans will pick themselves up off the floor and fly! Add to compare list Add to wishlist. kiss my grits! See my post “Control over Power”. 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